Mike Bloomberg is about to be unemployed for the second time in his professional life. The first was in August of 1981, when Saloman Brothers fired Bloomberg from the only full-time job he had ever known. The second time will be January 1, 2014, when he hands control of New York City over to the next mayor.

The cover story of this week’s TIME magazine is about what Bloomberg will do next, with a clear focus on his enormous wealth and his determination to spend it down changing the world to fit his vision. We live now in a new age of mega-philanthropy, when newly minted billionaires have enormous powers to influence politics and how we live our lives. To report the story, I travelled in late September with Bloomberg to Paris and London, where he reviewed grant proposals and launched new philanthropic efforts and met with British Prime Minister David Cameron.

Below are some additional excerpts from Bloomberg’s conversation with TIME in London.

On what he will do next:

I’ve said I’m not a consultant. I would want to own the company. I’m not a teacher. I want to learn, but that’s not my bag. I’m not an investor. I delegate that to others. I’m not an author. I wrote one book, did a book party, know what it’s like. I wrote every word in the book no matter what anybody says. But I’ve done it once. I want to do things. And I think the first answer to your questions is if you came to me and said, “I’m just retired or lost my job or whatever. What should I do?” My answer is wait a little while, a couple of months, and see what’s out there because of the things that will become available to you that you never ever even remotely thought about. And it would be a shame to commit yourself. And whatever’s available to you day one is going to be available two months later if it isn’t “So what?”

On how he approaches philanthropy:

I want to work on those things that others aren’t working on, where you can really make an impact and you can do groundbreaking work or set up the world for the next philanthropist or innovator to come along. So for example, smoking, nobody was working on that. AIDS lots of people are working on, but nobody’s working on obesity. Nobody’s working on traffic deaths. Malaria, yes, there are other people doing it, but at Johns Hopkins we’re trying to build a better mosquito, one that will drive out the old one but doesn’t carry the parasite. With [Bill] Gates, on polio I gave him $100 million. I gave him an award the other day, the Lasker Award, he and Melinda, and he had sent me an email. We had talked about polio before. It’s down to three countries: Nigeria, Afghanistan, and Pakistan. We’ve had 40-odd workers who have been giving out vaccine killed so far working on this project. If you could stamp out polio, it wouldn’t come back. If you don’t stamp it out, it will catch on, like tuberculosis is — in Africa tuberculosis all of a sudden has reared its head. It’s a disaster. All of a sudden. If you can — and why not do that when there’s plenty of money? Because a lot of people will be afraid to go in with the dangers and the fact that that last three countries is going to cost a half a billion dollars.

On the resistance to his efforts:

None of these fights are going to be easy. If it was easy, we wouldn’t have to have a fight. It would have been done a long time ago. But all of these things. Yes, the tobacco companies are strong. Yes, now they’re attacking with e-cigarettes, which are not great for you, incidentally. Don’t smoke them. Or obesity with full-sugar drinks and fast food cultures and that sort of thing. Okay, you know, if it was easy, it would have been solved and I wouldn’t be attacking it. These are good problems to have. And nobody thinks you’re going to win all the time. But just take a look. Gay marriage is as good an example as any. There’s a whole bunch of states now. And background checks for internet and gun show sales on guns, 15 states now have background checks. And in every one of those states, the suicide rate’s half the national average. It’s fascinating. Suicide, you have to get a gun quickly. There’s fewer guns on the streets. Chances are you don’t find the gun. You don’t commit suicide. You say, “I’ll do it tomorrow.” And you never get around to it, okay?